XXVII. Notes on a Recent Trip to Egypt

Abstract

At the outset the author described in some detail the geographical aspect of the country. He then mentioned the temples and monuments which he had visited, particularly noting the rock-materials of which they were composed. Some of these buildings were entirely of alabaster, formed as a secondary deposit in the caverns which had been hollowed in the Tertiary limestone, while others were composed of the limestone or the granite of Assouan, or of the Nubian sandstone. He then gave an account of various geological phenomena observed by him. One group of beds on the opposite side of the Nile from Assouan seemed to be identical lithologically with our own Carboniferous rooks, with the Arran section of which they might be compared on account of the way in which they had been altered by the neighbouring granite. The general similarity was heightened by the occurrence of beds of ironstone and carbonaceous deposits, contained charred plant-remains. Another highly interesting section showed an intrusive boss of quartz surrounded by mica-schist. The occurrence of a large number of blocks of the petrified wood of an exogenous tree in the loose sand overlying the nummulitic limestone near Cairo was also described, while overlying the petrified forest was a bed of sand containing numerous beautifully-rounded water-worn pebbles, mostly of quartz. It was not easy to account for the origin of these pebbles, as the nearest rocks containing quartz, which Mr. Neilson had seen, lay something like 600 miles further south. On the surface of the desert This 250-word extract was created in the absence of an abstract